Herpes Often Unknowingly Spread

Oct. 30, 2008 (Washington D.C.) -- Young women who don't know they have the virus that causes genital herpes could be unknowingly fueling the herpes epidemic, new research suggests.

Although they have no symptoms of the disease and have not been tested, many women are actively shedding the virus in their genital tracts, says Kenneth Fife, MD, of Indiana University School of Medicine in Indianapolis.

"They're often infectious and don't know it," he tells WebMD.

Nationwide, at least 45 million people 12 and older, or one out of five adolescents and adults, have genital herpes, according to the CDC. It's most often caused by herpes simplex virus type 2 (HSV-2).

Fife and colleagues studied 127 young women. They entered the study when they were 14 to 18 and followed for four to six years. Only three of the women had been diagnosed with genital herpes, and the rest hadn't been tested before.

Two-Thirds of Women Actively Shedding Virus

Over the course of the study, about one-fourth of the women who originally tested negative for HSV-2 subsequently tested positive.

But what was really of concern, Fife says, was that two-thirds of the women for whom genital swabs were available were actively shedding virus. "That's when they can spread the disease," he says.

Had the women not been in the study, they might never have been tested, Fife says. Most had no symptoms -- not even common symptoms like genital pain or vaginal discharge, which can be caused by a number of disorders, he says.

The research was presented at a joint meeting of the American Society for Microbiology and the Infectious Diseases Society of America.